nostr:npub1lh273a4wpkup00stw8dzqjvvrqrfdrv2v3v4t8pynuezlfe5vjnsnaa9nk's rationale is "see? I was right." That's it. But there are no "right and wrong" when it comes to OP_RETURN.
That being said, Wasabi only has to implement storing the message they need somewhere else, hashing it and then store the hash in a 40 byte OP_RETURN transaction. The client validates the message comparing its hash to the hash stored in Luke's 40 byte version of OP_RETURN, problem solved, everyone happy.
It's an easy solution and takes minutes to develop.